Process for making window-envelops.



G. W. SWIFT, 1R. PROCESS FOR MAKING WINDOW ENVELOPS. APPLICATION FILED uov.21. 19w.

1,276,282. Patented Aug. 20, 1918'.

3 SHEETS-SHEET I- G. W, SWIFT, JR. PROCESS FOR MAKING WINDOW EMVELOPS.

APPLICATION HLED NOV. 21. 1911.

1,276,282. Patented Aug. 20, 1918 3 SHEETS-SHEET 2- FIG: I?

Imwm

George lllswi 5,622; M W

a. w. SWIFT, 1B.

NG wmnow smvnors r PROCESS FOR MAKI OINILED novzlqeu. I a

. Patented Aug. 20, 1918.

APPLICATY! a snms-snm 3.

FIG; .12

a anine GEORGE 'W. SWIFT, 3B4, OF LBORDENTO'WIQ", NEW? J'PRQCESS FOR MAKING 1 71133301? =31? ELUEPS.

Specification of Letters Patent.

Patented ring. 26 iillilfi.

Application filed November 27, 1917. Serial No. 264134.

To all whom it may concern:

Be it known that I, GEORGE W. SWIF'Z, Jr., of Bordentown, in the county of Burlington and State of New Jersey, have invented a certain new and useful Process for Making /Vindow-Envelops, whereof the following is a specification, reference being had to the accompanying drawings.

In this art it has heretofore been the practice in the use of processes for continuously manufacturing window envelops from a progressing web to punch or cut perforations therein at suitable intervals. Simultaneously a transparent ,atch web is advanced and patches out there rom and properly applied to each of said perforations, in order to form a succession of Windows each covered by a transparent patch. Thereafter the web is cut to form individual envelop blanks each containing a patched window in proper position to permit the formation therefrom of the desired window envelope.

In order that the patches cut from the patch web may properly register with the perforations cut in the envelop web, care must be taken to accurately synchronize the motion of the two webs. I have found that difiiculty arises when it is thus attempted to continuously and evenly advance the envelop web perforated at intervals because of the large apertures required to make the windows. This is due to the unstcadiness of an envelop web thus perforated. Such web" is necessarily advanced under some tension, and when perforated by large transverse apertures at intervals, as has been practised in this art, it tends to stretch. This tendency to stretch produces an unsteady motion which prevents the accurate application of each patch to each window.

In order to overcome this difliculty according to my present invention, I have devised a scheme of operation by means of which the patch material is applied to parts of a moving envelop web which have no window openings, but in such relation to the web that when the web is subsequently perforated and folded and out to form indi vidual envelope, each envelop will contain a patch properly applied to and protecting its window. Accordingly, my process is characterized by the following steps, namely: the continuous progression of envelop material; the attachment to parts thereof while still intact of transparent patch material; the subsequent formation of window openings at proper intervals in said material andthe i'hlding and cutting of the material for the formation oi envelops, in the course of which the patch material required for each envelop is by such process of folding brought into proper relation to the window aperture to enable it to be secured in proper relation thereto.

This process of operation by which the patch material is applied to the envelop material before the window openings are formed, and whereby the formation of the envelop itself accomplishes the proper juxtaposition of the window patch to its window opening, is capable of being carried out by a variety of mechanisms. I will. briefly describe suitable mechanism for carrying it out.

In the accompanying drawings, Figure I,

is a diagrammatic view of the advancing envelop web with patches of window material successively applied. thereto.

Fig. II, is a view of the envelop blank cut therefrom. r

Fig. HE, is a cross sectional View showing the transfer position of the patch when the envelop is folded, whereby the said patch is brought into proper juxtaposition to be secured to the window envelop.

Fig. IV, is a simplified form of mechanisin for accomplishing the progress of the envelop web, showing the succession of groups of devices, whereby the successive steps of my process may be practised.

Figs. V, VL-Vll, and VH1, are detailed views of certain of these devices, as will hereafter be described.

Referring to Fig. IV, 1, is the roll of envelop material. As it unrolls, this material passes from the feed rolls 2, 2, to the trimming rolls 3, 3, where the edges of the en vclop web are trimmed for the formation of the side flaps. These mechanisms are welhknowi'i in the art.

The envelop web, which is still continuous and nnperforated, next passes over a curved table above which rotates a pres sure roll 6. lhese are the instrumontalities employed to apply patches of transparent window n'mterial to the unperit'oratcd envclop web at iropcr intervals. Upon reference to Fig. iv, it will be understood that the patch web roll 10, supplies the material for these patches. As it is advanced, it passes between the rolls 11, 11, where it reccives at intervals upon its lower surface an its upper surface opposite to the lower surface of the envelop web beneath which it is fed. From these cutting rolls each patch slides over the curved table 5, whereby it is led into contact with the lower surface of the envelop web. lit the same time the roller 6, effects a. depression of the envelop web by reason of pod T, which presses web against the gumlned lower edge patch, producing; adhesion of the edvencing envelop weh carrying these patches edhering to proper parts of posses between the cutting rolls 20, 2Q, Vi}, wherehy other parts of it are perforated with the f emotion of successive windows therein. These windows 21, are not in the ii'nniediete region of the previ ousiy opplied petches, but in such relation thereto that, as result of the subsequent steps by which is accomplished the formetion of lillfil envelop, the folding of tie new terisl will ultimately bring the petch in the desired relation to the window.

hue successive positions of the p .es on the envelop web are detemnined an while it 13 on unperforeted web,

nee in this art, in

feet the relation of the is more accurately determined than by processes heretofore in n ce. the patches are not ied to weo until after it is perby eoson which patches to the web After the window opening has seen out,

the envelop web continues to advance and as it t tween the rolls 25, .25, Vlll} adhesive is applied, to the lower side each window patch in e form of gum of which 2d, 2%, correspond. to the the window patch and 27, 2?, I short edges. Further advencing'the materiel posses between rolls 30, 30, '1 ill), theenvelop material 3 and e process of enveop forn'ifitlon begins. These rolls and the occonipenying' mechenism areshown in section in Fig. identical with similar envelop forming mechanism shown and described by me in Letters fizntent of the United States No. 866,978, granted me under date of Sep tember 2-14., 190?. it is, therefore, unnecessary for me again describe the operation of this mechanism, further than po nt out that the fol d or crease H where: th :owerc edge of the envelop is formed, takes place at a point which results in folding each patch to be subse- Will, and are substantially Lemme? in the region of its 10%? summed edge along the line -21, (see Fig. Ill). Following this fold the back of the envelop comes into its normal position in relation to the front of the envelop, so that the patch is now for the first time brought into its ulti-' mate relationship to the window of the envelop, the guinmed strips 26, 26, 27, 27, immediately occesioning the proper adhesion of the patch to the window opening which it is to protect. Thereafter, the process of envelop formation and completion proceeds as heretofore practised in the art. If reference be had to Fig. III, which is a longitudinal central section through the completed envelop blank, it will 'benoted that the patch 15', is adherent to the inside of theenvelop at 16, where its lower edge was originally gummed to it; at 17, which is the lower edge of the window petch where it carries one of the gummed strips 26; and et 18, which is the upper edge hereof, where it carries the other gummed strip 26.

From the foregoing understood that it is process that the envelop description it will be to characteristic of my web is not perfoingsuntil after the window materiel hos been applied to certain proper parts of it, and that thereafter the window openings are punched therein and the individual envelop blanks severed therefrom and folded: and that it is in the operation of envelop formation and not before, theteach patch no is'for the first time brought into proper relation to the window opening to which it is to 1 be permanently secured and which it is to protect. After the patch has adhered to the envelop by reason of the gummed strips 26, 26, Q7 527, there is nolonger any necessityof continuing; adhesion along the gummed line 12, and therefore employ a. temporary edhesive guthet this point.

Having thus described my invention, 1 no claim:

1. The process of making. window envelops which consists in continuously odvencin-gunperforated' envelop rneteriol; zipplying window the envelop materiel perforating other parts of the envelop material at intervals for the formation of window openings; and folding and cutting the material for envelop formation, whereby the folding operation brings 120 a patch of window material into proper relation to each. window opening.

2. lfhe process of making window envclops which consists in continuously edvancing unperforated envelop material; 1225 applying window material to parts only of the envelop material by e tern orery adhesive; perforating other ports 0' the envelop nmtcrial at intervals for the formation of window openings; and folding ondcutting no material to parts only of the material for envelop formation, whereby the folding operation brings a patch of window material into proper relation toeach window opening, where it is seeurecl by a permanent adhesive.

3. The process of making window envelops, which consists in progressing an endless web of unperfomted envelop material; applying to such unperforated envelop material at properly spaced intervals transpar ent wirulow patches; then perforating the envelop material at proper intervals for the formation of window openings; and folding and cutting the material, whereby each patch is brought into proper relation to the 1'' GEORGE W fisWIFT, JR.

Witnesses: J. HOLMES LONGSTREET, Wm. H. Coon. 

